Method of treating cellulosic materials with trimethylolphenol



Patented Jan. 24, 1950 METHOD OF TREATING CELLULOSIC MATE- .RIALS WITHTRIMETHYLOLPHENOL Nicolas Drisch and Item: Fays, Paris, France, al-

signors to Comptoir des Textiles Artiflciela, a corporation of France NoDrawing. Application February 23, 1946 8Q- rial No. 649,780. In FranceJune 5, 1944 Section 1, Public Law 690, August 8, 1946 Patent expiresJune 5, 1964 12 Claims.

This invention relates to the manufacture of artificial products derivedfrom cellulose. More particularly, it relates to a method of improvingthe physical properties of synthetic textiles derived from cellulosicmaterials. Specifically, it relates to treating the synthetic textilematerial in the form of dense masses.

Copending application Serial No. 649,777, filed on even date herewith,entitled Cellulose derivatives and process of preparing same," disclosesa process for preparing new cellulose derivatives, called resylcellulose, by the formation of bridge linkages between cellulose chainsby means of resiniferous compounds, more especial- 1y biorpolymethyloloxyaryls, and the general application of this process to themanufacture of variousproducts.

Copending application Serial No. 649,778, filed on even date herewith,entitled Shaped synthetic products and method of making same," andcopending application Serial No. 649,779, filed on even date herewith,entitled Method of treating preformed shaped structures," disclose theapplication of the aforementioned process to the manufacture ofsynthetic products, and particularly viscose rayon yarn.

In the process disclosed in the aforementioned applications, the bridgelinkages are converted into resiniform linkages by heating, preferablyin the presence of suitable catalysts. containing the resiniformlinkages are characterized inter alia by swelling to a degreeconsiderably lower than that of the untreated cellulosic material.

When the aforementioned processes were applied to dense masses ofartificial textiles, such as rolls of rayon goods or compressed bales ofstaple fiber, the thermal treatment was eifected by means of hot air.Such procedure did not produce materials which had substantially uniformproperties throughout the mass of the goods. Usually, the material atthe outside of the bale swelled in water materially less than thematerial at the center of the mass.

Additionally, the fiber was characterized by an undesirable yellowcoloration.

An object of this invention is to provide a new method of thermallytreating cellulosic materials containing free hydroxyl groups andimpregnated with a bior poly-functional resiniferous Products compoundwhich, under the influence of heat, will form resiniform bridge linkagesbetween cellulose chains.

Another object of this invention is to provide a method of thermallytreating dense masses of cellulosic materials containing free hydroxylgroups and impregnated with a bior poly-functional resiniferous compoundwhich, under the influence of heat, forms resiniform bridge linkagesbetween cellulose chains to impart improved and substantially uniformlyreduced swelling characteristics throughout the mass.

Other and additional objects will become apparent hereinafter.

The above objects are accomplished, in general, by subjecting densemasses of textile materials, comprising cellulosic material having freehydroxyl groups and impregnated with a bior poly-functional resiniferouscompound which, under the influence of heat, will form resiniform bridgelinkages between cellulose chains, to the action of dry saturated steamunder pressure. The dry steam serves as a heat carrier and has theadvantage of effectively and easily penetrating the dense mass.Preferably, the dry steam is deaerated and, preferably also, prior tothe treatment of the mass with the dry steam, the mass is subjected tothe action of a vacuum.

The details and manner of practicing the invention will become apparentby reference to the following specific examples, it being understoodthat these examples are merely illustrative embodiments of the inventionand that the scope thereof is not in any way limited thereto. Throughoutthe examples, the proportions of the ingredients are parts by weight.

Example 1 To a viscose solution having a cellulose content of 7% and acaustic soda content of 6.5% was added 15% (based on the cellulose) ofthe product of controlled (partial) condensation of trimethylolphenolobtained by heating the trimethylolphenol at from 96 C. to 98 C., in thepresence of lactic acid, for several hours, this product being dissolvedin its own weight of an aqueous 6% caustic soda solution. Afterhomogenization and ripening the resulting viscose to a salt number of 5,it was spun into an acid bath of the "Muller' type through a spinnerethaving 1000 orifices at a rate giving a unit standard of 4 denier(metric number 2250). The yarn was stretched, washed with water, andthen desulfured by an aqueous solution containing 10 grs. per liter ofsodium suliite. The desulfured yarn was thoroughly washed and thenimpregnated with an aqueous solution containing grs. per liter of ananion active derivative of a long chain fatty acid. The material was cutinto pieces 100 mm. long, which were subjected to an opening treatmentin an opener, and the resultant fiufi dried under a temperature in theneighborhood of 90 C. The staple fiber at this stage had a swelling inwater of the order of 85%.

The staple fiber was baled under pressure into identical bales of 100kg. One of the bales was introduced into a horizontal autoclave andsubjected to the action of a vacuum, the final pressure being 60 mm. ofmercury. Then dry steam, preferably de-aerated and under.2 kg. persquare centimeter pressure, was introduced into the autoclave andallowed to act for 2 hours. The temperature was 120 C. correspondin tothe pressure of 2 kg. per square centimeter. At the end of this periodof time, the swelling of the material in water was reduced to 45%uniformly throughout; the bale. The fiber had a slightly yellow color.

Another of the identical bales, prepared as previously described, washeated with hot air at 130 C. for 2 hours. At the end of this time, thefibers at the outside of the bale swelled in water 48%, while the fibersat the center of the bale swelled in water 75%. The fibers resultingfrom this treatment had a pronounced yellow color, specially at thesurface of the bale.

, Example 2 Staple fiber (regenerated cellulose) of 4 denier (metricnumber 2250) was treated in an aqueous bath containing 30 grs. per literof trimethylolphenol prepared according to the method of Manasse andLederer (Berichte der deutschen chemischen Gesellschaft, 1894, vol. 27,p. 2409). The fiber was passed into a drier, and after drying it had aswelling of 110%.

The fiber was compressed into bales of 100 kg., and a bale of materialwas treated with dry steam under a pressure of 2 kg. per squarecentimeter under the same conditions as those set forth in Example 1.The product of this treatment swelled 54% substantially uniformlythroughout the mass without any appreciable yellow coloration.

Herein, the term swelling or equivalent terminology is defined as thepercentage of water retained by the dry material after impregnation withwater and drying for minutes in a centrifugal drier cm. in diameter androtating at 3,000 R. P. M.

The trimethylolphenol utilized in Example 2 is prepared in accordancewith the method of Manasse and Lederer above referred to, wherein phenolis condensed with formaldehyde, in the form of formol, in the proportionof 3 mols of formaldehyde per phenol radical, in the presence of analkaline medium, such as caustic soda, lime, organic bases. etc., atmoderate temperatures, for example not exceeding 65 C., th reactionbeing completed in about 2 hours. At ordinary temperature (20 C.), thereaction will take 48 hours. The end of the reaction is marked bycomplete absorption of the formol. The alkali is then carefullyneutralized. Formation of resinous products must be avoided. Thereaction product is a mixture of the phenyl diand trl-alcohol, thelatter (trimethylolphenol) preponderating and being present in an amountof more than When a different phenolic derivative is employed as the rawmaterial, the poly-alcohol phenol is prepared in a similar manner tothat'previously described except that the quantity of formol isdetermined by calculation of the maximum number of methylol radicalswhich can be fixed to the nucleus of the phenolic derivative used. Theresulting product is a polymethylolphenol consisting essentially oftrimethylolphenol, as explained in co-pending application Serial No.649,777, above identified.

The partially condensed trimethylolphenol used in Example 1 is obtainedby a controlled condensation of the product produced above by theManasse and Lederer process. Specifically, the reaction product ofManasse and Lederer is condensed by heating it at from 96 to 98 C. forseveral hours in the presence of lactic acid, the final product beingsoluble in aqueous solutions of caustic soda, as fully described incopending application Serial No. 649,778.

The polymethylolphenols are the simplest of the resiniferous compoundswhich have proven to be the most suitable resiniferous compounds. Theinvention, however, is not restricted to polymethylolphenols. Ingeneral, any bior polyfunctional resiniferous compound, and moreespecially bior polymethyloloxyaryls, which in the presence of heat andpreferably in the presence of an acid catalyst form resiniform bridgelinkages by etherification of the hydroxy groups of the cellulosematerial and internal condensation, and having the following generalformula, can be used:

(CH OH).

in which R is an aryl group, either cyclic or polycyclic, R is an alkyl,aryl, acyl group or hydrogen, and n is at least 2. The radical R maycomprise two or more phenyl groups combined by direct saturation oftheir valences or by an oxygen, carbonyl, amine, hydrocarbon, etc.bridge. It may also comprise polycyclic groups themselves combined asshown above.

As is shown by the specific examples, the resiniferous compound may bebe incorporated into the solution from which the yarn is formed, or itmay be applied to a preformed yarn or fiber. When applied to a preformedstructure, the resiniferous compound is preferably applied in an aqueoussolution, though it can be applied from a nonaqueous solution asdisclosed in the aforementioned copending application Serial No.649,779.

The dry saturated steam employed in the process is preferablysubstantially free of oxygen, or the oxygen content is reduced to aminimum. Satisfactory results are obtained when de-aerated dry steam isused.

The temperature at which the reaction is carried out is not of greatimportance. Manifestly, it should not be so high that the cellulosicmaterial will be deleteriously afiected.

In the preferred embodiment of the invention, as shown by the specificexamples, the reaction is carried out in the absence of a catalyst.However, an acid catalyst can be used if desired, and, when used, thetemperature and times of the thermal treatment are correlated to givethe best results. When an acid catalyst is to be used in procedureswherein the reslniferous compound is incorporated in situ during thespinning of the filament, the catalyst can be incorporated as disclosedin copending application Serial No. 649,778. When the catalyst is to beincorporated in a preformed structure, it can be incorporated asdisclosed in copending application Serial No. 649,779.

French application No. 490,205, for Process of treating absorbenttextiles especially those of regenerated cellulose, discloses a processof treating cellulose hydrate materials with steam for reducing theswelling of such materials in water. The processes of the aforementionedapplications Serial Nos. 649,777, 649,778, and 649,779, also result inmaterially reducing the swelling of the product. The reduction inswelling of cellulosic materials has been the subject of research formany years and, though it has not yet been determined if the action ofthe steam and the resiniferous compounds are cumulative, nevertheless ithas been determined that to obtain the same final swelling the operatingtemperature is lower, or the duration of the treatment is shorter, orthe catalyst present is less active, in the case of thermal treatmentwith dry saturated steam as herein described than that with hot air.

Though the invention has been described in connection with dense massesof staple fiber, it is not restricted thereto since it is manifest thatthe invention can be applied to other masses. The invention can beapplied to rolls of fabric made of yarn having the resiniferous reagentincorporated therein. Similarly, the invention can be applied to denseskeins of yarn in which the resiniferous reagent has been incorporated.

The dense mass is preferably formed of regenerated cellulose yarn orfiber obtained by the viscose process. However, the invention is notrestricted thereto. The yarn or fiber may be obtained from solutions ofcellulosic derivatives containing free hydroxyl groups, such ashydroxyalkyl or glycol cellulose, cellulose carboxylic acids, slightlyetherified methyl and ethyl cellulose, etc. It also can be obtained fromdry spinning of cellulosic derivatives.

Since it is obvious that various changes and modifications may be madein the above description without departing from the nature or spiritthereof, this invention is not restricted thereto except as set forth inthe appended claims.

We claim:

1. A method which comprises subjecting a dense mass of cellulosicmaterial, having free hydroxyl groups and having incorporated therein anon-resinous polymethylolphenol consisting es- .sentially of atrimethylolphenol which upon heating will form resinous bridge linkagesbetween the cellulose chains, to dry saturated steam under pressure.

2. A method which comprises subjecting a dense mass of cellulosicmaterial, having free hydroxyl groups and having incorporated therein anonresinous polymethylolphenol consisting essentially of atrimethylolphenol which upon heating will form resinous bridge linkagesbetween the cellulose chains, to dry saturated steam substantially freeof oxygen and under pressure.

3. A method which comprises subjecting a dense mass of cellulosicmaterial, having free hydroxyl groups and having incorporated therein anonresinous polymethylolphenol consisting essentially of atrimethylolphenol which upon heating will form resinous bridge linkagesbetween the cellulose chains, to dry de-aerated saturated steam underpressure.

4. A method which comprises subjecting a dense mass of cellulosicmaterial, having free hydroxyl groups and having incorporated therein anonresinous polymethylolphenol consisting essentially of atrimethylolphenol which upon heating will formresinous bridge linkagesbetween the cellulose chains, to a vacuum, and then subjecting theresulting mass to dry saturated steam under pressure.

5. A method which comprises subjecting a dense mass or cellulosicmaterial, having free hydroxyl groups and having incorporated therein anonresinous polymethylolphenol consisting essentially of atrimethylolphenol which upon heating will form resinous bridge linkagesbetween the cellulose chains, to a vacuum, and then subjecting theresulting mass to dry saturated steam substantially free of oxygen andunder pressure.

6. A method which comprises subjecting a dense mass of cellulosicmaterial, having free hydroxyl groups and having incorporated therein anonresinous polymethylolphenol consisting essentially of atrimethylolphenol which upon heating will form resinous bridge linkagesbetween the cellulose chains, to a vacuum, and then subjecting theresulting mass to dry de-aerated saturated steam under pressure.

7. A method which comprises subjecting a bale of staple regeneratedcellulose rayon fibers, having incorporated therein a non-resinouspolymethylolphenol consisting essentially of a trimethylolphenol whichupon heating will form resinous bridge linkages between the cellulosechains, to dry saturated steam under pressure.

8. A method which comprises subjecting a bale of staple regeneratedcellulose rayon fibers, having incorporated therein a non-resinouspolymethylolphenol consisting essentiallyof a trimethylolphenol whichupon heating will form resinous bridge linkages between the cellulosechains, to dry saturated steam substantially free of oxygen and underpressure.

9. A method which comprises subjecting a bale oi. staple regeneratedcellulose rayon fibers, having incorporated therein a non-resinouspolymethylolphenol consisting essentially of a trimethylolphenol whichupon heating will form resinous bridge linkages between the cellulosechains. to dryde-aerated saturated steam under pressure.

10. A method which comprises subjecting a bale of staple regeneratedcellulose rayon fibers, having incorporated therein a non-resinouspolymethylolphenol consisting essentially of a trimethylolphenol whichupon heating will form resinous bridge linkages between the cellulosechains, to a vacuum, and then subjecting the resulting bale to drysaturated steam under pressure.

11. A method which comprises subjecting a bale of staple regeneratedcellulose rayon fibers, having incorporated therein a non-resinouspolymethylolphenol consisting essentially of a trimethylolphenol whichupon heating will form resinous bridge linkages between the cellulosechains, to a vacuum, and then subjecting the resulting bale to drysaturated steam substantially free of oxygen and under pressure.

12. A method which comprises subjecting a bale of staple regeneratedcellulose rayon fibers, having incorporated therein a non-resinouspolymethylolphenol consisting essentially of a trimethylolphenol whichupon heating will form resinous bridge linkages between the cellulosechains, to a 8 vacuum. and then subjecting the resulting bale NumberName Date to dry de-aerated saturated steam under pressure- 2,190,672Meharg Feb. 20, 1940 NICOLAS DRISCH. 2,288,695 Fuller July 7, 1942 RENEFAYS. 2,338,983 Thackston et a1. Jan. 11, 1944 I REFERENCES CITEDFOREIGN PATENTS Number Country Date gggfi m the 437,642 Great BritainNov. 4, 1935 484,691 Great Britain Aug. 4, 1936 UN TE STATES PATENTS 10547,846 Great Britain Sept. 15, 1942 Numb? Name Date 92 OTHER REFERENCESI $1 ,22 Emai 3? 1 g Granger: Condensation of Phenols with Form- 2088227Battye g; July 1937 aldehyde," I, and Eng. Chem, vol. 24, No. 4 (April2,093,651 Widmer Sept.21,1937 l93m'pages 442-447- 2 .13'7,465 ThackstonNov. 22, 1938

1. A METHOD WHICH COMPRISES SUBJECTING A DENSE MASS OF CELLULOSICMATERIAL, HAVING FREE HYDROXYL GROUPS AND HAVING INCORPORATED THEREIN ANON-RESINOUS POLYMETHYLOLPHENOL CONSISTING ESSENTIALLY OF ATRIMETHYLOLPHENOL WHICH UPON HEATING WILL FORM RESINOUS BRIDGE LINKAGESBETWEEN THE CELLULOSE CHAINS, TO DRY SATURATED STEAM UNDER PRESSURE.